3GPP Long Term Evolution, LTE, is the fourth-generation mobile communication technology standard developed within the 3rd Generation Partnership Project, 3GPP, to improve the Universal Mobile Telecommunication System, UMTS, standard to cope with future requirements in terms of improved services such as higher data rates, improved efficiency, and lowered costs. In a typical cellular radio system, wireless devices or terminals also known as mobile stations and/or User Equipment units, UEs, communicate via a Radio Access Network, RAN, to one or more core networks. The Universal Terrestrial Radio Access Network, UTRAN, is the radio access network of a UMTS and Evolved UTRAN, E-UTRAN, is the radio access network of an LTE system. In a UTRAN and an E-UTRAN, a UE is wirelessly connected to a Radio Base Station, RBS, commonly referred to as a NodeB, NB, in UMTS, and as an evolved NodeB, eNB or eNodeB, in LTE. An RBS is a general term for a radio network node capable of transmitting radio signals to a UE and receiving signals transmitted by a UE.
Future communication systems are expected to, in many situations, be based on wireless ad hoc networks instead of, or in combination with, today's cellular communication approach with a central node, to which every device within reach of the central node should transmit the data. The terms ad hoc or Device-to Device, D2D, networking typically refers to a system of mutually communicating network elements that together form a network requiring little or no planning.
A mesh network is per definition a network topology in which each node relays data for the network and wherein all nodes cooperate in the distribution of data in the network. Mesh networks can be considered a type of an ad-hoc network. Thus, mesh networks are closely related to mobile ad hoc networks, MANETs, although MANETs also must also deal with problems introduced by the mobility of the nodes.
In mesh networks, routing is used in order to transmit a packet of data from a source node to a target node via interconnected nodes acting as relays between source and target. In general, routing can be defined as the act of moving information from a source node to a target node via one or more intermediate nodes in a communication network. In wired systems, where typically the bit error rates are negligible and any collisions are immediately detected upon transmission, resulting in a fixed per-link routing cost, routing is performed on the Internet Protocol, IP, level, using IP addresses.
Wireless routing, on the other hand, differs from wired in that wireless channels are significantly less reliable and more variable. The cost of routing a packet through a certain link is no longer constant but instead depending on the channel between the link nodes. In order to optimize performance with respect to either sparse radio spectrum resources, and/or packet latency, routing is preferably performed on a lower layer where knowledge of the wireless channel properties exists. In its simplest form, knowledge of a successful transmission of a packet along the route is obtained by the receiver transmitting an Acknowledgement, ACK, message back to the transmitter.
FIG. 1a shows an example scenario relevant for the present disclosure. In FIG. 1a the access points or nodes 10a-10f may be a subset of a number of nodes in an ad hoc or mesh network. Packets may be delivered from node 10a to node 10b and node 10a needs to choose a routing either via 10c, 10d or 10e, or a subset of 10c-e (i.e. choose two or three routes for simultaneous transmission) to 10b. 
In prior art wireless meshed networks, such as according to the standard IEEE 802.11s, the path setup is performed by an Ad hoc On-Demand Distance Vector, AODV, using the airtime link metric, ATLM, which is an estimation of the total transmission “air time” for a packet.
The modulation and coding scheme for a given metric is e.g. based on reception of previous acknowledgement/non-acknowledgement, ACK/NACK, messages or from sounding requests that are independent from mesh signaling. Hence, from a system capacity point of view this is a very cumbersome and inaccurate procedure, in particular in a mesh network. Furthermore, the information regarding link quality that a transmitting node will get by receiving ACK/NACK:s from the receiving node is very rough. Furthermore, building relevant statistics from ACK/NACK:s may take some time and during the build-up phase there is a significant risk for unnecessary packet delays on the IP level that may reduce the Quality of Service in delay sensitive applications. Additionally, in a dynamic network the statistics is quickly outdated, which is also implying suboptimal performance.
In wireless mesh network one possibility is to choose routing based on channel quality for respective possible route to use. Such methods are described e.g. in U.S. Pat. No. 7,881,206 B2 disclosing a health aware routing protocol on the network that considers a combination of link quality and node health/residual lifetime metrics in the calculation of the desirability of nodes and links between nodes as parts of an overall route. In some cases also adaptation of Modulation and Coding Scheme, MCS, for the chosen route is also determined, as e.g. in International Patent Application WO2010083661 A1.
Furthermore, United States Patent Application US2010329134 A1 describes a method including determining a channel quality indication (CQI) value for each of a plurality of wireless sub-channels, discarding any of the CQI values older than a threshold time, leaving a set of current CQI values, determining a percentile CQI value based on the set of current CQI values and transmitting the percentile CQI value to an infrastructure node.
However, in some applications, for instance due to the respective link quality for the possible routes e.g. 10a-10c or 10a-10d, it might not be possible to fit in the received packet from 10f in a single route transmission, and fragmentation implies time delay of the packet.
Then an alternative could be to transmit the packet over different nodes as suggested in WO2010/053347. When transmitting a packet over different nodes, the scheduler routes a received data packet over several different routes, either as a duplicate of the packet, split it in sub packets and transmitted in FDM fashion or in a Multiple Input Multiple Output, MIMO, fashion, i.e. the data packet is split in two halves and sent over two different routes as sub-streams on the same time-frequency resources.
However, existing methods for path selection in wireless mesh networks do not fully exploit the advantages of multiple path routing.